package com.itheima.filter;

import com.alibaba.fastjson.JSONObject;
import com.itheima.pojo.Result;
import com.itheima.utils.JwtUtils;
import jakarta.servlet.*;
import jakarta.servlet.annotation.WebFilter;
import jakarta.servlet.http.HttpServletRequest;
import jakarta.servlet.http.HttpServletResponse;
import lombok.extern.slf4j.Slf4j;
import org.springframework.util.StringUtils;

import java.io.IOException;

//@WebFilter("/*")
@Slf4j
public class LoginCheckFilter implements Filter {
    @Override
    public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain) throws IOException, ServletException {

        HttpServletRequest req = (HttpServletRequest) servletRequest;
        HttpServletResponse resp = (HttpServletResponse) servletResponse;
//        1.获取请求url
        String rul = req.getRequestURL().toString();
//        2.判断请求url中是否包含login，如果包含，放行
        if (rul.contains("login")) {
            filterChain.doFilter(servletRequest, servletResponse);
            return;
        }
//        3.获取请求头中的令牌token
        String jwt = req.getHeader("token");
//        4.判断令牌首是否存在，如果不存在，返回错误结果
        if(!StringUtils.hasLength(jwt))
        {
            log.info("请求头为空");
            Result error = Result.error("NOT_LOGIN");
            String notLogin = JSONObject.toJSONString(error);
            resp.getWriter().write(notLogin);
            return;
        }
//        5.解析token，若失败，，返回错误结果
        try {
            JwtUtils.parseJWT(jwt);
        } catch (Exception e) {
            log.info("解析令牌失败");
            Result error = Result.error("NOT_LOGIN");
            String notLogin = JSONObject.toJSONString(error);
            resp.getWriter().write(notLogin);
        }
        filterChain.doFilter(servletRequest, servletResponse);

    }
}
